OBJECTIVE Epidemiological studies relating maternal 25-hydroxyvitamin D (25OHD) with gestational diabetes mellitus (GDM) and mode of delivery have shown controversial results. We examined if maternal 25OHD status was associated with plasma glucose concentrations, risks of GDM and caesarean section in the Growing Up in Singapore Towards healthy Outcomes (GUSTO) study. METHODS Plasma 25OHD conc...

OBJECTIVE To identify 25 hydroxyvitamin D (250HD) levels in Thai pregnant women with gestational diabetes and nongestational diabetes. MATERIAL AND METHOD This prospective study was conducted on 197 pregnant women at Rajavithi Hospital, a tertiary care medical center in Bangkok from October 2010 to July 2011. Plasma 25 hydroxyvitamin D concentration and HbA1c level during the 75 g OGTT in ges...

Endemic hypovitaminosis D contributes to osteoporosis development. However, variation in 25-hydroxyvitamin D (25OHD) measurement is reported and confounds the diagnosis of vitamin D insufficiency/deficiency. This report emphasizes the marked variability observed in serum 25OHD measurements between laboratories.Initially, postmenopausal women had serum 25OHD determinations: 42 in laboratory A, 2...

BACKGROUND The impact of season when determining a serum 25-hydroxyvitamin D (S-25OHD) cut-off level for optimal bone health is unknown. OBJECTIVE To investigate the relative importance of S-25OHD for bone mineral density (BMD) by season. METHODS A subcohort of 5002 Swedish women (mean age 68 years), randomly selected from a large population-based longitudinal cohort study with repeat dieta...

INTRODUCTION Serum 25-hydroxyvitamin D (25OHD) deficiency (<50 nmol/l or 20 ng/ml) has been associated with increased blood pressure (BP) in observational studies. A paucity of data on this relationship is available in Latin American or child populations. This study investigates the association between 25OHD levels and BP in adolescents at risk for vitamin D deficiency in 2 Peruvian settings. ...

CONTEXT There is a controversy regarding the definition of vitamin D insufficiency as it relates to bone health. OBJECTIVE The objective of the study was to examine the evidence for a threshold value of serum 25-hydroxyvitamin D (25OHD) that defines vitamin D insufficiency as it relates to bone health. DESIGN AND PARTICIPANTS This was a cross-sectional analysis of baseline data in 488 elder...

OBJECTIVES This study was designed to determine mean serum concentrations of 25-hydroxyvitamin D (25OHD) in postmenopausal women with low bone mineral density (BMD), to find the cutoff of parathormone (PTH) elevation, and to evaluate the correlation 25OHD with BMD, biochemical parameters and vertebral fracture presence. METHODS Transversal study, with collection of 25OHD and PTH, and determin...

Low vitamin D status has been implicated in several chronic medical conditions and unfavorable health outcomes. Our goal was to investigate whether serum 25-hydroxyvitamin D (25OHD) levels are a potentially modifiable risk factor for anemia in a nationally representative cohort of community-dwelling individuals in the United States. We performed a cross-sectional study of 5456 individuals (≥17 ...

CONTEXT There is no consensus on the definition of vitamin D deficiency for bone health based on serum 25-hydroxyvitamin D (25OHD) levels. OBJECTIVE Our objective was to determine whether thresholds exist for associations between 25OHD levels and bone outcomes and if low 25OHD levels have adverse effects on bone health. DESIGN This is a cross-sectional study. PARTICIPANTS This study inclu...

Multiple sclerosis (MS) incidence and serum 25-hydroxyvitamin D (25OHD) levels vary by race/ethnicity. We examined the consistency of beneficial effects of 25OHD and/or sun exposure for MS risk across multiple racial/ethnic groups. We recruited incident MS cases and controls (blacks 116 cases/131 controls; Hispanics 183/197; whites 247/267) from the membership of Kaiser Permanente Southern Cali...